Problem: The expression $3y^2-y-24$ can be written as $(3y + a)(y + b),$ where $a$ and $b$ are integers. What is $a - b$?
Explanation: We see that $3y^2-y-24 = (3y + 8)(y - 3)$, thus $a = 8$ and $b = -3$. Hence, $a - b = \boxed{11}.$